1. FIELD OF THE INVENTION
The present invention relates to polymeric casting mold structures, and more particularly to polymer casting molds which include metallic fillers and the method for forming same.
2. DESCRIPTION OF THE PRIOR ART
Recent developments in the material sciences has brought forth a variety of materials useful in general application. Amongst those are the materials in the polyester resin group, various polyurethane, vinyl chloride polymers as well as the various phenol formaldehyde resins and epoxy resins. The resins, in particular, are well suited for low cost fabrication, resulting in useful articles which are inert, of substantial strength and hardness, and well suited for machining and mechanical finishing. This material stability, its inert response to chemicals of general exposure, and its tolerance to heat and structural load have led to a wide acceptance of these resins in household use. In consequence many of the bath fixtures of a typical household are now of one of the various polymers which, because of their fabrication convenience, have led to a virtual explosion in the variety of shapes, functions and competing sources that are obtained.
One group of bath fixtures is the cultured marble group comprising articles like sink tops, bath tubs and the like. Typically, articles of this kind are formed by casting with their surface finish directly determined by the surface qualities of the casting mold. Since the same conveniences in casting are also useful in the production of the mold, the mold itself is often made from the same or similar material. This material similarity between the casting mold and the article cast therein and the exothermic reaction often associated with the casting often significantly limit the mold life. Moreover, close control over the mold release coatings and the surface finish of the mold are inherent to such material similarity.
Thus, inexpensive techniques for modifying the material properties of the mold surface are extensively sought and it is one such technique that is disclosed herein.